Gynoecium MCQ - Practice Questions with Answers

Parts of a Flower - Gynoecium

• Gynoecium is the female reproductive whorl of the flower.
• It is made up of one or more carpels/pistils/megasporophyll.
• A carpel consists of stigma, style and ovary.
• Ovary is the enlarged basal part on which the elongated tube called style is present.
• The style connects the ovary to the stigma.
• The stigma present at the tip is receptive surface for the pollen grains.
• Ovary contains one or more ovules attached to a flattened cushion-like placenta. 
• When more than one one carpels are present and they are free, the condition is called apocarpous, e.g., lotus and rose.
• When more than one carpels are present and they are fused, the condition is called syncarpous, e.g., mustard and tomato.

1. Monocarpellary : It is a gynoecium with a single carpel, e.g., Bean.
2. Bicarpellary : It is the presence of two carpels in a gynoecium. e.g., Helianthus.
3. Tricarpellary : It is the presence of three carpels in a gynoecium e.g., Cocos.
4. Tetracarpellary : It is the presence of four carpels in a gynoecium. e.g., Cotton.
5. Pentacarpellary : It is the presence of five carpels in a gynoecium. e.g., Hibiscus.
6. Multicarpellary : It is the presence of many carpels in a gynoecium. e.g., Annona.

Locules in the Ovary:

• The ovary encloses one to many chambers called the locules. Based on the number of locules, the ovary may be described as follows :

1. Unilocular : Ovary with one locule. e.g., Dolichos.
2. Bilocular : Ovary with two locules. e.g., Solanum.
3. Trilocular : Ovary with three locules. e.g., Allium.
4. Tetralocular : Ovary with four locules. e.g., Datura.
5. Pentalocular : Ovary with five locules. e.g., Hibiscus.
6. Multilocular : Ovary with many locules. e.g., Abutilon.

Style:

• The stalk like-structure present above the ovary is called the style. 
• The style may be long (Datura) or short (grasses) or absent (Papaver).
•  In the family umbelliferae (apiaceae) the base of the style is swollen and forms a structure called stylopodium.
• There are three types of styles as described below :

1. Terminal style : If the style arises from terminal part of the ovary, it is called terminal style, e.g., Datura, Hibiscus and Solanum.
2. Lateral style : If the style arises from one side of the ovary, it is called lateral style, e.g., Mango.
3. Gynobasic style : If the style arises from the base of the ovary it is called gynobasic style, e.g., Ocimum, Salvia.
    

Stigma:

• The terminal receptive portion of the style is called the stigma. 
• It receives pollen grains during pollination. 
• Usually the lobes of the stigma corresponds to the number of carpels. 
• Accordingly the stigma may be unifid, bifid, trifid, tetrafid, pentafid or multifid.

Types of Stigma:

• Capitate : Round stigma. e.g., Hibiscus.
• Forked : Divided stigma. e.g., Tridax.
• Feathery : Brush like stigma. e.g., Grasses.